1. Field of the Invention
The present invention relates to a system and method for designing and fabricating circuits. Specifically, the present invention relates to a system and method for automatically modifying wire sizes to, for example, eliminate undesirable edges or “jogs” in a wiring tool.
2. Description of Background
The process of designing and fabricating a circuit, e.g., with the use of a circuit mask design editor, may include the use of an auto wiring tool. The auto wiring tool fabricates wires using the input design and rules based on the technology being employed and the physical demands placed on the circuit. For example, a rule that may be employed during the fabrication process is a minimum feature distance requirement which ensures that every wire and source is wide enough to function properly. Those of ordinary skill in the art will appreciate that the wiring tool may be automated as well as manually operated.
Many times the wires created with a wiring tool include edges or jogs. A jog is an edge that is shorter than the minimum width of the metal used to make the wire. Often times, jogs create unnecessary edges or corners, that can be detrimental to the yield of the design because they can require added mask compensation shapes which cause what is known as a blooming effect during optical proximity correction or OPC.
One solution for this problem is to have the user manually edit the size of the wire or resulting shape after production. Another solution is to run a wire straightening program after the wires and jogs are created with the auto wiring tool. This may also be applied during post processing and may be run on the entire design. It is clear that these solutions are not favorable or cost effective. The disadvantages to these solutions include the inefficiencies created by the additional post processing step and the additional costs associated with adding steps to the production process.
A further solution to eliminating unwanted jogs is through the use of cost analysis. A cost value is assigned to each wire placement option indicating the cost of the jog that would result in the masking process corresponding to that placement, wherein a greater cost indicates that a more undesirable jog would be created in the masking process than would be created by a placement assigned a lesser cost. The placement having the lowest cost of the plurality of possible placements is selected. This solution provides a good solution to minimizing small jogs, however, if the wire width and length is small relative to the connecting wire width, it could be beneficial and effective to extend the wire width of the routed wire to match that of the wire being routed to.